The present invention relates to reducing and/or vertically shifting characters as they are printed in a matrix printer, and more particularly the invention relates to the production of footnotes, indexes, subscripts, superscripts, to be affixed to characters slightly above or below the regular line of printing. Characters are produced and generated under utilization of pulses from a data source and under further utilization of a character generator, translating the data from the source into signals that can be used directly for generating physical character representations, whereby moreover a matrix printhead is to be used for printing lines. Such printheads may include one or more print needles or styli arranged in one or more columns, and printing is to be carried in one or several print passes. Generally speaking the invention relates to a matrix printer of the type that permits accomodation of certain specialized tasks of the type outlined above.
Text printing under utilization of a suitably prepared data source is limited to some extent by the construction and operational principles involved in matrix printers. The limits are variable to some extent and certain steps can be taken to overcome certain limits and reset them in an operational manner. For example matrix printers can be used in a regular manner as originally contemplated for high speed printing, bearing in mind that the quality of the print has certain limitations here, but for the particular cost involved is adequate in some extent. 0n the other hand near-letter quality printing is not directly possible with a matrix printer unless certain additional steps are taken, which permit for example the printing of additional dots in between two dots printed in the high speed mode. Inherently of course high quality printing requires additional print operations, so that the overall speed is reduced.
German printed patent application No. 2,516,835 suggests in a different context printing in both directions without shift and using a pattern in which characters disposed one above the other are printed. This obtains through synchronization of the character generator with a clock just ahead of the magnetic coil of the print head.
German printed patent No. 2,515,557 discloses a modification in a matrix print operation, such that any character is amenable to be printed in a normal pattern and configuration or in a laterally expanded or broad version. This feature obtains through the connection of feed back connected registers being further connected to the output of the character generator, there being one register provided for each stylus. Accordingly for normal printing certain points or dots of the matrix being designed to accomodate the broad print version are supressed.
These various teachings of the prior art have their advantage within the contemplated limitations of the design and employment purpose. The known structure does not permit printing of all possible characters that may appear in a text.